Discussion Forum



1)

A colourless water-soluble solid A on heating gives equimolar quantities of B and C  . B gives dense white fumes with HCl and C does so with  NH3. B gives a brown precipitate with Nessler's reagent and C gives a white precipitate with nitrates of Ag+, Pb+ and Hg+. A is 


A) $NH_{4}Cl$

B) $NH_{4}CO_{3}$

C) $NH_{4}NO_{2}$

D) $FeSO_{4}$

Answer:

Option A

Explanation:

$NH_{4}Cl $   $\underrightarrow{\triangle}$ $NH_{3}+HCl$

A(colourless)                        B     & C ( equimolar quantities)

$NH_{3}+HCl \rightarrow NH_{4}Cl $

 B                         dense white fumes

 $NH_{3}+2K_{2}[HgI_{4}]+3KOH \rightarrow H_{2}NHgO.HgI+7KI+H_{2}O$

                Nessler's reagent                               Brown ppt. Iodine of Milinon's base

$HCl+MNO_{3}\rightarrow MCl+HNO_{3}$

  C                                 white ppt.

                                     (M= Ag+, Pb2+, Hg+)